Irish Daily Mail columnist Paul Drury has said he was stimulating public opinion in his comment piece about Denis O’Brien which is now the subject of a defamation action.
He rejected suggestions by senior counsel Paul O'Higgins that he was "exempt" from verifying facts for the article.
Mr Drury said the role of newspapers was to inform, entertain and stimulate public opinion.
Mr Drury said he was stimulating public opinion in his piece.
He said he was entitled to do that, he had spent his life fighting for the right to do that and would continue to do so.
Mr Drury was being asked about research he carried out for the article.
Senior Counsel Paul O'Higgins said quotes extracted from a Forbes article about Denis O’Bien could be done "by any computer literate 12-year-old".
Mr Drury agreed but said he did not think many Irish people would bother to look up Forbes magazine and he believed some of the information was highly relevant to the piece he was writing as it concerned Digicel business in Haiti.
He said not all opinion pieces required independent verification of facts which were already in the public domain.
He agreed he had not telephoned reporter Charlie Bird to ask how long he had spent with Mr O’Brien.
He believed the interview had been featured on RTÉ’s Six-One News but Mr O'Higgins put it to him that it never appeared on that bulletin.
Mr Drury said it was his recollection it was on that bulletin but it could have been the RTÉ Nine News.
In any case he believed it would have been repeated on many bulletins.
He did not ring Digicel to confirm any facts and said he was commenting on what he had seen on television and this was not a case for original investigative reporting.
That was a completely different type of journalism, he said.
He rejected a suggestion that he was "prepared to pedal anything to readers" because he did not know the facts. He replied: "I know what I saw and what the RTÉ viewers saw."
He said he believed if anyone was going to get access to prime time television it should have been an Irish NGO or charity and not a businessman.
When asked what influence Mr O’Brien would have had over how much air time he got on RTÉ, Mr Drury said obviously RTÉ would make that decision but Mr O'Brien had gone to extensive efforts to facilitate the interview.
He said Digicel had helped secure a seat on a plane for former RTÉ reporter Charlie Bird ahead of relief workers.
Mr O’Higgins said it was plain that Mr Bird had sought the interview but Mr Drury said "It takes two to tango".
It was put to him that Mr O’Brien said he spent about 12 minutes in Mr Birds company for the entire week.
Mr Drury said in the context of a major disaster it was still a significant amount of time.
He denied there was dishonesty about the article. Mr O Higgins said Mr Drury had written about Mr O Brien "spending so much time telling Charlie Bird all that he was doing "whereas the transcript showed he only mentioned one thing and that "had to be dragged out of him".
He said the remainder of the interview was about the need for EU intervention.
Mr Drury said he had never suggested he had used the Haitian tragedy to his advantage but was using the interview to his advantage.
He said being involved with charities could be advantageous to wealthy men. Mr O’Higgins suggested he was throwing everything in to discredit Mr O’Brien.
He accused him of relentless bias and lack of honesty in the piece.
The paper's former Editor in Chief Paul Field also gave evidence.
He said he had written the headline on the piece and the decision to publish had been his and his alone.
He denied the decision to publish the column was an attempt to put a diferent angle on the Haiti coverage to make it more scurrilous.
He described as irrelevant the fact that he previously worked for the National Inquirer.
It was put to him that the National Inquirer had once published photographs of Elvis Presley in his coffin and of Whitney Houston's house referring to the use of crack cocaine.
He said he was five years old when the Elvis Presley picture was used.
Senior Counsel Jim O’Callaghan said a Reuters report after his appointment as editor of the National Inquirer described a "crack team of British tabloid journalists who are going to go for the jugular".
Mr Field said he worked for many other publications and may have written in different styles at different times but what did not change were his journalistic standards.
Earlier, the jury heard evidence concerning the date Mr Bird arrived in Haiti.
Dominic McSorley from Concern yesterday gave evidence to say he arrived on the same plane as Mr Bird on 17 January 2010.
However, television reports showed Mr Bird in Haiti on 15 January.
The confusion prompted Ms Justice Elizabeth Dunne to comment, "maybe we put too much faith in RTÉ".
When the case resumed this morning the jury was told Mr McSorley had mixed up his dates, leading to the confusion.
Both sides agreed that Mr Bird had in fact travelled to Haiti on 15 January.